Improvement in tabs for gang-saws



H. DISSTON.

TABS FOR GANG-SAWS.

No. 181,421. Patented Aug-.22. 1876.

%.J y////////////////.. V//////////////// N. 9117513, PHOTO-UTNDGRAPNER,WASHINGTON D. C.

TATES PATENT FFIC.

HENRY DISSTON, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN TABS FOR GANG-SAWS.

Specification forming part of Letters Patent N0. 18 L421, dated August22, 1876 application filed July 10, 1876.

To all whom it may concern:

Be it known that I, HENRY DIssToN, of Philadelphia, Pennsylvania, haveinvented an Improvement in Tabs for Gang Saws, of which the following isa specification: I

The object of my invention is the secure attachment to a mill-saw bladeof the tabs which are seized by the books or stirrups appertaining tosaws of this class.

In the accompanying drawing, Figure 1 represents the'upper portion of amill-saw blade as it appears when prepared for attachment of theimproved tab; Fig. 2, the same with the tab attached; Fig. 3, atransverse section; Fig. 4, a sectional plan on the line 1 2, and Fig. 5a sectional view of the tab detached from the blade.

The blade is of the usual construction, with this exception, that aconcave recess, :20, is formed in the front or toothed edge of theblade, both at the upper and lower end of the same. The tab B consistsof a single strip of steel, bent in the middle at m, so as to embraceand fit accurately to the blade to which the tab is riveted. At thepoint Where the tab is bent it is made convex on the inside, asindicated by the line y y in Fig. 4, and this conveX portion of the tabis arranged to fit snugly in the above-mentioned concave recess :20 of-11ame to this specification in the the blade. Tabs as usually attachedto sawblades rely upon the rivets as mediums for resisting the strainsto which they are subjected; but the tearing of the tabs from the bladesin spite of the rivets is a common occurrence. The greatest tensilestrain is exerted on mill-saw blades at the front or toothed edge of thesame, and it is for the purpose of resisting this strain that the convexportion 3 of the tab is adapted to the recess 00 of the blade, both atthe upper and lower end of the same. The rivets are consequentlyrelieved from a great portion of the strain, and the tab is mostsecurely fastened to the blade where the latter is subjected to thegreatest resistance. 7

I claim as my invention- The within-described tab, composed of a stripof steel, bent as described, and having at the bend a convex portion, y,adapted to a recess, 00, in the blade, as set forth.

In testimony whereof I have signed my presence of two subscribingwitnesses.

, HENRY DISSTON. Witnesses GEO. S. GANDY,

A. H. SHOEMAKER.

